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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.nereids.properties;

import org.apache.doris.nereids.exceptions.UnboundException;
import org.apache.doris.nereids.trees.expressions.Slot;

import com.google.common.collect.ImmutableList;

import java.util.List;

/**
 * LogicalPlan must compute and return non-null LogicalProperties without exception,
 * so UnboundRelation.computeLogicalProperties() return a UnboundLogicalProperties temporary.
 */
public class UnboundLogicalProperties extends LogicalProperties {
    public static final UnboundLogicalProperties INSTANCE = new UnboundLogicalProperties();

    private UnboundLogicalProperties() {
        super(ImmutableList::of, () -> DataTrait.EMPTY_TRAIT);
    }

    @Override
    public List<Slot> getOutput() {
        throw new UnboundException("getOutput");
    }

    @Override
    public boolean equals(Object o) {
        return o instanceof UnboundLogicalProperties;
    }

    @Override
    public int hashCode() {
        return 0;
    }
}
